LifeCode: A Deployed Application for Automated Medical Coding

Abstract

LifeCode is a natural language processing (NLP) and expert system that extracts demographic and clinical information from free-text clinical records. The initial application of LifeCode is for the emergency medicine clinical specialty. An application for diagnostic radiology went into production in October 2000. The LifeCode NLP engine uses a large number of specialist readers whose particular output are combined at various levels to form an integrated picture of the patient's medical condition(s), course of treatment, and disposition. The LifeCode expert system performs the tasks of combining complementary information, deleting redundant information, assessing the level of medical risk and level of service represented in the clinical record, and producing an output that is appropriate for input to an electronic medical record (EMR) system or a hospital information system. Because of the critical nature of the tasks, LifeCode has a unique "self-awareness" feature that enables it to recognize the limits of its competence and, thus, ask for assistance from a human expert when faced with information that is beyond the bounds of its competence. The LifeCode NLP and expert systems reside in various delivery packages, including online transaction processing, a web browser interface, and an automated speech recognition (ASR) interface.